/*
	This file is part of the OdinMS Maple Story Server
    Copyright (C) 2008 Patrick Huy <patrick.huy@frz.cc> 
                       Matthias Butz <matze@odinms.de>
                       Jan Christian Meyer <vimes@odinms.de>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License version 3
    as published by the Free Software Foundation. You may not use, modify
    or distribute this program under any other version of the
    GNU Affero General Public License.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

package net.sf.odinms.tools;

import java.io.Serializable;
import java.util.AbstractMap;
import java.util.AbstractSet;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

/**
 * Provides a strongly-typed map of keys to values.
 * 
 * @author Frz
 * @since Revision 589
 * @version 1.0
 * 
 * @param <K> The type of the keys.
 * @param <V> The type of the values.
 */
public class ArrayMap<K, V> extends AbstractMap<K, V> implements Serializable {
	static final long serialVersionUID = 9179541993413738569L;
	/**
	 * Provides a strongly typed mapping of a key to a value.
	 * 
	 * @author Frz
	 * @since Revision 589
	 * @version 1.0
	 * 
	 * @param <K> The type of the key.
	 * @param <V> The type of the value.
	 */
	static class Entry<K, V> implements Map.Entry<K, V>, Serializable {
		static final long serialVersionUID = 9179541993413738569L;
		protected K key;
		protected V value;

		/**
		 * Class constructor
		 * 
		 * @param key Name of the key
		 * @param value The value.
		 */
		public Entry(K key, V value) {
			this.key = key;
			this.value = value;
		}

		/**
		 * Gets the key.
		 * 
		 * @return The key.
		 */
		public K getKey() {
			return key;
		}

		/**
		 * Gets the value.
		 * 
		 * @return The value.
		 */
		public V getValue() {
			return value;
		}

		/**
		 * Sets a new value.
		 * 
		 * @return The old value.
		 */
		public V setValue(V newValue) {
			V oldValue = value;
			value = newValue;
			return oldValue;
		}

		/**
		 * Compares two Entries for equality.
		 * 
		 * @return <code>True</code> if the two Entries are equal,
		 *         <code>False</code> otherwise.
		 */
		@Override
		@SuppressWarnings("unchecked")
		public boolean equals(Object o) {
			if (!(o instanceof Map.Entry)) {
				return false;
			}
			Map.Entry e = (Map.Entry) o;
			return (key == null ? e.getKey() == null : key.equals(e.getKey())) &&
				(value == null ? e.getValue() == null : value.equals(e.getValue()));
		}

		/**
		 * @see java.lang.Object#hashCode()
		 */
		@Override
		public int hashCode() {
			int keyHash = (key == null ? 0 : key.hashCode());
			int valueHash = (value == null ? 0 : value.hashCode());
			return keyHash ^ valueHash;
		}

		/**
		 * @see java.lang.Object#toString()
		 */
		@Override
		public String toString() {
			return key + "=" + value;
		}
	}

	private Set<? extends java.util.Map.Entry<K, V>> entries = null;

	private ArrayList<Entry<K, V>> list;

	/**
	 * Class constructor
	 */
	public ArrayMap() {
		list = new ArrayList<Entry<K, V>>();
	}

	/**
	 * Class constructor.
	 * 
	 * @param map The <code>java.util.Map</code> containing keys and values to
	 *            import.
	 */
	public ArrayMap(Map<K, V> map) {
		list = new ArrayList<Entry<K, V>>();
		putAll(map);
	}

	/**
	 * Class constructor.
	 * 
	 * @param initialCapacity The initial size of the ArrayMap.
	 */
	public ArrayMap(int initialCapacity) {
		list = new ArrayList<Entry<K, V>>(initialCapacity);
	}

	/**
	 * Returns a set of entries in this ArrayList.
	 * 
	 * @return The entries in a <code>java.util.Set</code> instance.
	 */
	@Override
	@SuppressWarnings("unchecked")
	public Set<java.util.Map.Entry<K, V>> entrySet() {
		if (entries == null) {
			entries = new AbstractSet<Entry<K, V>>() {
				@Override
				public void clear() {
					throw new UnsupportedOperationException();
				}

				@Override
				public Iterator<Entry<K, V>> iterator() {
					return list.iterator();
				}

				@Override
				public int size() {
					return list.size();
				}
			};
		}
		return (Set<java.util.Map.Entry<K, V>>) entries;
	}

	/**
	 * Puts a key/value pair into the ArrayMap.
	 * 
	 * @param key The key of <code>value</code>
	 * @param value The value to insert into the ArrayMap.
	 * @return <code>null</code> if no entry was replaced, the value replaced
	 *         otherwise.
	 */
	@Override
	public V put(K key, V value) {
		int size = list.size();
		Entry<K, V> entry = null;
		int i;
		if (key == null) {
			for (i = 0; i < size; i++) {
				entry = (list.get(i));
				if (entry.getKey() == null) {
					break;
				}
			}
		} else {
			for (i = 0; i < size; i++) {
				entry = (list.get(i));
				if (key.equals(entry.getKey())) {
					break;
				}
			}
		}
		V oldValue = null;
		if (i < size) {
			oldValue = entry.getValue();
			entry.setValue(value);
		} else {
			list.add(new Entry<K, V>(key, value));
		}
		return oldValue;
	}
}
